Selective telephone system.



No. 820,063. PATENTED my a, may N. s. McKmsiEY & A 3. NELSON.SELEUTIVBTBLEPHG SYSTEM.

AFPLEGAYIG FILE $113215 1934 V 5 SHEETS-SHEET 1,

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f5. 41 M w Var- 2 m. 820,063. 7 PATBNTED MAY 8, 1906.

N. S. MGKINSEY & A. R. NELSON.

SELECTIVE TELEPH ONB SYSTEM. arrmenmw' 12111; mm: 15, 1904.

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SELECTIVE TBLEPHU NB SYSTEM. urmonmn nun 1113315, 1904.

all. llillisxllilllli rsla PATENTED MAY 8, 1906. McKINSEY & A. R.NELSON.

GT TELEPHONE SYSTEM. APPL an rum? mm: 15, 1904.

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in "E m WNW! W 7 ..H V 1 1 .J M -M fi. V K I P-W i V k 0 i imi 3PATENTED MAY a, 1905! 1%. s. MGKINSEY &' A. R. NELSON.

SELECTIVE TELEPHOfiE SYSTEM.

' and ANTON R. Nurses, citizens of the United,

' of the door of the telephonebox whic shows stood by eonsidsimultaneousliy Whenever the line "of Lassen and'State of Californimhavein- "and the art immediately joiu'rier, H h inescoiitroller and of Ytherewith.

7 and thwart of the clockwork, mechanism,

UNITED STATES PATENT OFFICE.

SELECTIVE TELEPHORE SYSTEM.

No. 820,063. Beatification of Letters Patent. Patented May 8, 1906.

Lppiluetion filed June 15. 194. Serial No. 212.648.

To alt whom it my concern:

Be it known that we, Nospm S. MeKmsnr States, residing at Susanville, inthe county vented certain new and useful Improvements in SelectiveTelephone Sytems, of which the following is a specification. a

This invention relates to an improved selective tele hone'system, the ooect of the invention oing to provide a system by which a considerablenumber of telephones can beplaced onthe same line, so thet finy partycan call ii any other arty on the 'ne' without the ai of a centrestation and in which the talking shall he secret and free. frominterrhption or intrusion by. the other. parties on the line. 7 J

' In the accompanying drawings, Figure I is .adiagrammatical view of thesystem. Fig. 2 is a broken front elevation of one of the tele hoses, thedoor being thrown open and bro en away. .'3 is s. front elevation of thereer ortion o the telephone, the main portion 0 the mechanism beingremoved and the wires at theback of the telephone hein filifiwn indotted lines, Fig. 4 1's in vjertioa sectionof the u per ortionof thetelephone. Fig. 5 is a detail ver ical section; show n thebutton-carrier in different position from, hot in Fig. 4. Fi 6 is afrontelevation showing. the interior of the bell. Fig.7 is alreniii" frontelevation of the cloekwork inechsnrsm 5 5? the same 1g. 8 is-a frontview oi that ortion;

the busy indicator.-

9 is a rear elevation of the button-carrier showin also the clockworkmechanism in side elevation and, showing the electrieal' connectionbetween the "clockwork mechanism and the bottom 10 is a rear view of aportion of V the parts connected Fig. 1 1 is afront elevation showvingin detail the circular series of contact-pins connec therewith. 12is a'sicie'view me 0 operation" 0 V a The natureof the system 7 be; bestunder: its method of operation 1 wit "thedetails ofconstru'w tion. Thefo owingare the principal steps zi scriber taking down his receiverobtains control of the line. He thereby starts synchro- -nous clockworkmechanisms, one in each telephone, the starting of these clockwork mech-"aiiisms preventing all the other subscribers getting on the line in thesame way as did the calling subscriber. These mechanisms ve ingsubscriber pressing one die number of theother telephones. The clockworkmesh anisi'ns so restarted are all again arrested extent, do ending"upon the telephonselooted. T e belhcircuits in the callers and theselected party's telephones and in no because the rem-novel of hisreceiver i thi'ew onra shunt around the hammer-conhaififlfllflsbell-circuit, continuously ener- "the bell-magnets. The called partyseii rings until he takes down his receiver the eellingl'rsubscriber tookdown his receiver, he also t ew of a shunt which normally shunted thereceiver, and he thereby obtaiiied theuse of the receiver. 7 The calledobtained the, use of the receiver. None of the. other arties can throw05 the corree're fore none of them can use their receivers; eiso noneofigigm can close Itheir bell:- ueirsuit orprimary ta -circuit. encet ejtalkingis secret and urgnterrupted. V

. Gena-cl character of the eystem.,The sysfifteen subscribers, adaptablefor any number within reasonable limits, the mechanism of each telephonein the system be' the same. For the sskeof illustration'in 'ig. 1 thetelephones of solosc ei's Nos. 1, 10, and '15 are shown, the

Nos? and 10 being shown diagrammatically in detail and the othertelephones of the line connect all the telephones of the system. f Ofthese thewire lfis grounded at .on'eehd, osshown at3, havingthereinamain aresistance-S. This resistance '18 not in use, any sub- .4and, isgrester thalrthat-hf y'rseeonda talkin a e object being soon stopand are started again by the ca push-buttons, each" corresponding to oneof fetter they have advanced to a greater or less whenesimilar shunt is,thrown on. When.

other are closed; but the caller's hell does not i party on taking downhis receiver threw off a corresponding shunt in his telephone and sosfiending s nuts in their telephones, and t tem here shownis sup osed tobe for a line of though the system is L mid anisms of thetelepho'nes ofSubscribers "emitted. jTh'ere. are two line-wires 1 I which the groundto the talking-currents. At each telephone there is a bridge between thewires 1 and 2, consistin of a wire 6, magnet-coils 7, and a wire 8. incethe wire 1 is grounded, while the wire 2 is not normall grounded, andsince the magnet-coils 7 are a l on brid es between the wires 1 and 2,it is evident t at' under the action of a spring-plate 15, so that 31,and slidin vertica ly, on studs an arm 16, projecting rearwardly fromsaid hook, first presses against the bent lower end of theline-controller 12, then passesinto and through a recessed or cut-outportion 17 of the end of said controller, and then presses against aspring-finger '18, secured u on said controller, movin said finger upwarto contact with the end of the sprin -contact 11. The line-controller 12is normally held in position to be actuated by the arm 16 by reason of astud 19, extending forwardly from a wheel 20, hereinafter described,engaging the u per end of the gontroller. One break in tlie line fromthe wire 8 to the ground isthus closed. The other break is also closedas follows: The line-controller 12 is pivoted upon a horizontal shaft 21on the frame 22 of a clockwork mechanism suitably supported within thetelephonefbox 10, having a train of gears 23 actuated by a mainspring 24and controlled byanescapement 25 and escapement-wheel 26. The line fromthe ground therefore extends through said line-controller to saidclockwork mechanism. By a wire 27 said clockwork mechanism iselectrically connected with the metallic support or rim 28 of abutton-carrier 29, of insulating material, as wood. Said rim isyoke-shaped, having lateral arms 30 exten ing down within the sides ofthe telephone-box, the lower ends of said arms bei slotted, as shown at-32 ro 'ecting inwar y from the sides of said ox.

ateral guides 33 are also provided to guide the button-carrier initsvertical movement. It may be here stated that in addition to the wire 27leadinglfrom the clockwork mechanism to the meta lic rim of saidbutton-carrier, there areother wires 34, fourteen in number,

corresponding to the other fourteen telephones in the system and leadingfrom contact-pins, 35 to buttons 36 on the carrier, these fifteen wiresbeing connected in a single cable. When now the receiver is taken downfrom the automatic-hook, so that said hook rises, it releases thebutton-carrier, which had the arm then swings to the left point which wemay'call since they pass the stationary point at the been held down,with said automatic book, by a link 37, booked at its lower end aroundsaid automatic hook and at its upper end around a bracket 38, projectingrearwardly from the button-carrier. The button-carrier being free torise does so under the action of a spring 39, attached to the rear endof said bracket and also to a hook 40 in the top of the telephone-box.This upward motion of the button-carrier brings its metallic rim 28 intocontact with a contact-plate 41, se-

' cured to the under side of the top of the box and extending downwardltherefrom. This contact-plate is connecte with the wire 8, which leadsto the line-wire 2. It will thus be seen that any subscriber removinghis receiver from the automatic hook will immediately connect saidline-wire 2 with the ground, and since the line-wire 2 is connected withthe line-wire 1 in multiple by the wires 8 and 6 and the coils 7 ofamagnet in each telephone the effect of any subscriber takingownhisreceiver is to energize the magnet 7 in each telephone of the system,thereby drawing up its armature 42. This armature 42 is carried by theends of arms 43 44 mounted on a rock-shaft 45, havin bearings in theframe of the clockwork mec anism, and the movement of the armatureswings said arms. One arm 43 has a hook 46 extending therefrom, which inthe normal position of the clockwork mechanism engages a rearwardlextendi stop-pin 47 on the wheelZO of tli clockwor and prevents saidwheel 20 revolving, As soon, however, as the line is closed'to theground from the main wire 2 and all the ma ets are energized these books46 are lifted om the stop-pins 47, and all the wheels 20 commence torevolve under the action of the mains rings 24. However, after revolvinga very s ort distance, the wheels stop for the fpllowing reason: Eachwheel 20 gears with a pinion 48 on a shaft 4), having mounted thereonthe escapement-wheel 26, the proportion of the pinion 48 to thegearwheel 20.being such that the escapementwheel 26 makes ei htrevolutionsto one revolution of the whee 20. The shaft 490i thisescapement-wheel 26 has a bar 50 secured thereon, and the ends of thisbar are adapted to be engaged by a hook 51 on the lower end of thearrn43, when the magnet is energized and the upper end of said arm is drawnto the right toward said magnet. The lower end of and the hook 51 movesinto the path of the bar 50, so that as the 'esoa ement-wheel revolvesone end of said bar strikes said ,hooked end and the wheel is arrested.It is obvious that there" are sixteen equidistant points on thecircumference ITO of the wheel 20 passing any given stationary points ofarrest,

times at which the ends of the bar 50 can be so that when the wheel 7throngh about one thirty-second of a revoiut Ringehg saga-4n thisposition the wheelfi stem passing through a metallic-plate 56 and aflange 57 on the inner end of the stem.

wardagainst the action of the spring 39,

' upon the b htton-oarner; being no longerheld.

have anges 58 and afeisolqeeted ,on the carbeen ushedln oeu Y W offiiteein eontaet-pins whielr ET-7' 6 orally connected by 34 wanniesm oone ofthe circular series, butwhiehficon thefront of the door o 1 thetelephone-hex,

numhers, 1here are fi but o'n'e' of them corres pressed each ofthem isimmediately beneath escapes,

arm 43; The stop-pin 47 is placed seam;

vary with the num er of the telephone. These pins 35and 6G areanangediii a circle on insulatin material 62 adjacent *to thetongue 59, so t atsaid'tongue passes orerand contacts with each pin msuoces s ion 'fThe-end of the ton" eisisi'opedinwardiyto the rear edge, so 5 at itsadvancing 'eslge ea'rf'readil pass onto or over the pin,

half-way between two of these oints of ar revolved tion it is arrestedby one end of the bar 50, impinging against the hooked end of the arm 7e3, theniagnetslstili being energized.

remains anti the calling. subscriber the teiephone in the systemwithwhioh he wisheszfto cq munioate. This he does by pressing one oTourteen ush=hnttons 54 on and i 'preferably 'distingaished f bysuitable en buttons shown; 7 ding'to the number of that articular teepJhone is a fixed nor" utton; The 'uttons 'corffii ond ing' the otherto hones of the systein are push-buttons. *Eae; 'push buttonfi has aWhen the push-button selected is pressed'inward,-th1s flange S?- pnssesagainst the wooden buttonsearrief 29 and pushes it in which normal?draws the button-carrier forward as as, upward. This causes themetalhorini '28 of the button-carrier to slip past or behind thedepending plate 41,

down b said-plate rises under the action of the s ring 39.Theigtationhry buttons 36' rier that when the buttoncarrier is deacorresponding push -button 54.- -'Therefore when any one of theseh-battons if the utton-carrier to be re eased fronithe p ate 41 and tospring upward, the con riding stationa button 36 rise op -e, must thestem of t o 'jnsh button so posh and its flange58 the flange 57 of thepush-button and'lifiii against withdrawal. Contact broken between thebutton-oarrierrirri andithejplate 41, the magnets are deenergized, thehboh atr the lower end of thearm 43' is withdrawn- 7 re, and joapeninkwheelfih an thewheel 2fil are. to revolve. The line to'thegroundgwhioh' thus been broken. by 'theeepathtio'niefe plate in from theam of the be m in hrekenfnntil with thewheeizmtoaehesthst in thetelephone seieeted. It wi hforei that there were fourteeneostaet pinstionaig buttons; but inaddition tothesefeiirteen t ere is a fifteenthoontact-pinfiEsiini 'lar in all r outs to the others'and forniingnegated by a wire 87 with the heii-ciroui't and primarytransmitter-circuit of the telephone.

t 0 7 oured tf s e'P'f spring-colitis??? the position of this 68 in theseariisrn to said wire 8 by the" following route: the tongue 59,contact-Q35; wire 34, stationary buttonlsfi, pus lrutton 54',platerfifi, inetalliestrip 63, secured on the in-' tie-41 it passes fromsaid clockwork ner siee'efflthe door; upper hin e 64 for said a 7 doorg'a'rfidwirejfi to wire 8. T e energizizn of the'magnets throws thehooked lower on of the arm 43 into the path of the next arriving andofthe bar 50, so that before the esca enientrwhe'el has revolved throu11 oneha iire'volution and before the whee 28 has risvifeithfiu hone-sixteenth of a re'voiu- V tirinffiie seid W eel is arrested. .Thetongue igsgfieienti broad to insure the arrest of the wlifbe ore thetongue has left that 0011+ tootin which by its contact with the tongue"elose the. line -to the ground. The clockwork meehanism is new again atrest, and

the niagnets are now all ener ized. The ene cailin -sub-- "of themagnets of steiephone closes hiSbGll-GiICUlh, for theme-titre 42completes the circuit by contaet the ooresfifi of the magnets. V This isas follows: battery 67, wire 68,

'et-cores 66, armature 42, clockworkt gn t f rne' 22,controlling-leveriZ, arm 16, automatic book 14, base 69,- wire {10, wire2'' wire 72, binding post 73, bell-hammer 74, con.- taot-sto '25 post78', wire 79, wire 80; o .olosir'e of this circuit would start thebellringmg in the caningthe subseribers telephone were it not that the};

i'talnn' down of t forthejoll owing reason: The sprunge receiverprevents the beli j late "15,

eases, up the autoniat'le 'f insulated material 81 se Y i. iiiiiiiiii no7, is'seeured to and eleotncaliy eonn withi'the base or suppoit fiQfdlfSaid tomatio hook? Theiiepres si en ofthi gpi g-eontflt 82 normallymaintains it'bu't of contact with a second or upper spring-content 84,separated therefrom by material 85; but when theoalhngwliier T26; coils77 of the bellwhisk h 4 is 13, wire 70, base 69, automatic subseribertakes down his receiver these two springs 82 and 84 are thereby allowedto contact with each other. Ihis causes the current from the battery 67instead of passing intermittently through the hammer 7 4 of the bell topa continuous y thr ugh t 00115 of the magnet as follows; from thebattery, as before to base 69, contact 82. contact 84, wire 86, step 75,wire 76, c il 77, and so as before to the battery, This acts as a shuntto the intermittently-closed line bet en the not 7 3 and stop 75. Saidcoils are there: ore constantly ener 'zed, and the hammer is drawn uagainst t shell, whlch no longer rings. he bOllrBlI'Gllll? of thecalled-sub: scri er's telephone is closed a follows: hai tery 67, ire68, magnet-co 6, a mature 4;, elockwo k=freme 22, too 0 5 contactpin 60,wire 87, wire 72, bell.- amrner 74, and so as before to the battery.Tbls bell rings until the called subscriber takes down h s roceiv er,when the same. shunt is thrown on ener hung the bell-magnets c ntmuouslvand rawing up the hammer against the bell, The talkingwtrauite-Beforedescribing in detail the talki g=circuits it may be stated that a novelprincip e is hereintrog uced of pla ing the primary talk -c rou t inmulti-- ple with the bell-circuit. he same bette 67, which provides thecurrent for the hel circuit, provides the current for the pr nce talkmeir 'nt, the current hem divide art 0 it asslng through the be -magnetsand part t rough the transmi t r. For th purpose the transmitter 88,wire 105, and r mary wire of the iHduBt'iDIP-CGil 89 are plaeexi betweenwires 90 91, connected with the wires 79 and 72. Hence the rimltrytelking=circuits are the same as the ell-eh= suite with the abovechange, which is the ome both for the calling and for the calledsubscribers telephones. The secondary talki g-circuit 15 as follows:line=wire 1, Wire 6 to the eallmg=subscrihers telephone, wire 93,seoondar wire of the induction coil 89, wire 94, con sneer 95, wire 96receiver oak l4, 16, hue-controller 12, elockwork frame 22, tongue 59,pin 85, wire 34, stationary button 36, push-button 5 4, plate 56, st ip63, hinge '64, wire 65, wire 8, line=wire 2,

wire 8 of the eallecl subscribers telephone,

plate .41, rim 28, wire 27, clockwork-.fyame 22, tongue 59, contact-pin60 wire 87, wire 71, receiver 13, wire 96, e user 95, secondary wire ofthe inductiomcoil 89, wire 93; wire 6', line-wire 1.

The shunt or the raceiuenwB wh le the secondary to king-circuit, as wellas the pr many circuits, is complete, this of itself would not allow: oftalkie? In each tele hone the receiver is normal y shunted, u it is because these shunts are thrown off in the celli and called subscriberstelephones that to ng is possible between them. This shunt consists of awire 98. leading from the wire 96 to a contaetrstop 99 for the ha nmer.Normally the hammer rests against this stop and the shunt is on; butwhen the belLcircuits are closed either through the wire 87,

as in the called Subscriber's telephone, or through the line-controller12. as in that of the calling subscriber, then the shunt is off and thereceiver is in use, it is to be noted that the brid es of the othersubscribers can also be closeg at any time by taking down the receiver;Although the automatic hook does not make contact with the lineoontroller yet a contact is made between the rim 28 aml the plate 41,and the bridge iscempleteii as follows: wire 6, wire 93, secondary wireof induction-coil 89, condenser 95, wire 96, receiver 13, wire 70,spring-contacts 82 S4, wir 6, stop 75, wire 76, coils 77, llldlng P st 7,'wir 79, Wire bat y 67, ire Q8,

egne corcs 66, arm ure 43 Wire 27, mm .28, plate 41, Wire ,8.Nevertheless such other subscriber cannot intrude on the line for hisreceiver is shunted, and he cannot remove the shunt.

Th cont of th ltM=-W U the i g subscriber takes his receiver down, histime matic hook moves the line-controller 12 into contact (by thegpyingsfinger 18) with the spring-contact 11, and so it remains so longa his re er is of the heels, thus c osin one break in his line to thepupil. At the same time the magnets oi el the tele bones are energized,the other break in his 'no to he gr und being' als los d- T i starts thecl ckwork mechanisms of all the tele: Phones, and the forward ovement oft e other wheels 43 causes all the studs 19 to pass Over the controllers12, so that said other controllers 1B are no longer held by said studsin position to be engaged by the arm 16 en the automatic hooks and to bemoved up to bring the springrfinger 18 into contact with thespring-contact 11, Hence no other suh= scriber can make the necessaryclosure in the local circuit, this closure being made either through thewire 87 or through the line=eon= treller- Only one conversat on allowedamiheut 4% least a the ZinerWhen a subscriber has gb-.

taine possession of the line and has called up one g artv. he cannotcall up a second arty Wi hnut releasing the line, for the such:

utton oer-resounding to the second party will not lock with the fixedbutton; but the flanges Will strike against each other without looking.To converse with a se ond party, he must release the button-carrier, andthis he can nly o by h ging up he eiver, whereupon theline-controller isreleased and the line isfree- When he line iehus the feet is intimatedin each telephone n t e fgh lowing manner: A lever IDQ l3 piv ted at i supp end upon the inner sid f the door of the telsphon'edacx and c rriesaplate 1'31 so that said letters are concealed behind a When the line isut into use, the leversIBII' word "Busy 2ov to kill the groum when themetslli'c'tallii connectin 3o ing a. series of telephones, twoline-Wires; one

tern, means in each bridge for controlling its 0 through the 4 5 to killthe ground When the metallic talkingconnecting the other line-wire withthe'firs} 5 5 ing a, series of telephones, two line-wires, one 1' 69tons, means in each bridge for 'con'iirollgiits scopes having'thereonthe letters B U "8 Y, spaced from esch ether. An arm 102 projectsresrwsrdly from the lever 180 and is normally engaged by theline-controller 12,

piste 103 in an opening in the door. Said plate 103 has openings 104,spaced from each other the width of the letters, and said letters arenormally hidden behind these spsees.

of the other telep iones are no longer 7 by the controllers 12 of saidtelephones "and drop, thus bringing said letters opposite to" theopenings in the plate 103, so thudithe appears therest. We claim i. Aselective telephone system comp ing s series of telephones, twoline-wires connected to the ound, e resistance the en G- circuit isclosed, bridges between a wires atthe respective telephones" 7 tom,means in each bridgefer ens i telephone, and means et'es'ch tslsphos forthemther line -wire with the ground, w ereby all the bridges are placedin milliiiple on e circuit through the lineivires and ground,substantially as described,

2. A selective telephone system conipristhe connected to the ground, aresistance therein to kill the ground when the metallic telling circuitis closed, bridgesbetween the linewires at the respective telephones ofthe svstelephones, and means at each telephone for connecting the otherline-wire with the first linerwire through the ground, whereby ell'thebridges are placed in multiple on a circuit inc-wires and ground,substantielly as described. is

3. A selective telephone system comprising a series of telephones, twoline-wires, one connected to the ground, a resistance therein circuit isclosed, bridges between the linewires at the respective telephones ofthe systens, magnets in said bridges controlling telephones, and menusat each telephonefori line-wire through the ground, whereby rent throughthe line-wiresenergizes ell the magnets, substantially as described.

4. A selective telephone system compris connected to the ground, sresistance therein W tek ill the ground when the metallic circuit isclosed, bridges I between V the line wires stthe respective telephonesof the systelephone, e broken line ctnesieh fisleplione ,from the otherline-wire to the firstline-jvire:

through the ground, end means, sunsisv work mechanisms, and inesns,

for closing s break in said line, substantially as described;

5. A selective telephone system ccinpris ing a. series of telephones,two line-wires, one connected to the wound, a. resistance therein tolrill the ground when the metallic tulkingcircuit is closed, bridgesbetween the line- Wires at the respective telephones of the sys tone, s,magnet in each bridge, clockwork controlled by ssid insgnei, a brokenline at each telephone from the other line-Wire to the ground, means,actuated by "'the'rernovsl of the recciverlroni the hook, for closing sbreak in said line, thereby controlling the magnets and sterling theclockreied by cuis ne, im-

initisl movement of ss'iid'fi s is preventing the like closure in theother telephones 'by the reinovel of the receiver iroui' the hook,substantially as described. "6, In'an apparatus of the characterdescribed, a series of telephones, two linewvlres, one connected to thegrossed, s resistance therein to kill the ground when the metallictalking-circuitis closed, bridges between the line-Wires at therespective telephones of the system, inesns operetsble at eachteleplu'ine when said bridge is closed for controlling said telephone,and means at each telephone for connecting the other line-Wire with thefirst line-wire through the ground, siib'si'einiisliy as described.

7. In eniippnretus of the character dcscribed, the eombination of twoline-wires,

' uteri by the release of the automatic hook for rendering saidline-controller operative to close a break in the broken line to theground end rseens actuated with the closing cl salil break for renderingall the other line-control lers unres onsive to the corres endingautonistic hoo s, substantially as d i serihedi selective telephonesvsieni comprising two line -wires, bridges tberebetwesn at severalstations to ferns the secondary felling-circuit, each bridge'heving twobreaks i -herein, a receiver and secondary coil in each bridge, meansfor closing one of said breaks in any bridge by the removal of thereceiver iron its book, means for closing the other breslrin thebridgeat the celling ssoscribers nsues by these-1d removal of the receiver,and means for closing said other break at the celiessshscriesrsststioscontrollable select lively from o distsni station, substantially asdescribed,

9. A selective telephone ing two linevrires, brid es erebetween sit theremoval of the receiver lrom the hoeli,

the severe ststions to orin the seccedsry one of which is connected tothe ground, s re-' roe i'IO

sistem coinpiis t talking-circuit, each bridge having two breakstherein, a receiver and secondary coil in each bridge, means for closingone of said breaks in any bridge by the removal of the receiver from itshook, means for closing the other break in the bridge at thecalling-subscriber's station by the said removal of the receiver, and.clockwork mechanism at each station, and means operated thereby andselectively ro controllable at the calling-subscribers telephone, forclosing said other break at the called-subscribers station,substantially as described.

10. A selective telephone system comprising two line-wires, bridgestherebetween at the several stations, an electromagnet in each bridge, abell-ringing circuit at the bridge at each station having a breaktherein, and having also two parallel branches, each having a breaktherein, means for closing the former break by the energizing of themagnet, means for closing one of the latter breaks by the removal of thereceiver from its hook, and means for closin the other of the latterbreaks controllab e from a distant station,

substantially as described.

11. A selective telephone svstem comprising two line-wires, brid estherebetween at the several stations, an e ectromagnet in each bridge, abell-ringing circuit at the bridge at each station having a breaktherein, and having also two parallel branches, each having a breaktherein, means for closing the former break by the energizing of themagnet, means 3 5 for closing one of the latter breaks by the removal ofthe receiver from its hook, means, actuated by the said removal, forpreventing the like closure in the other telephones of the s stem, andmeans for closin the other of t e latter breaks controllable i rom adistant station, substantial] as described.

12. A selective telephone s stem comprising two line-wires, brid es terebetween at the several stations, an e ectromagnet in each 5 bridge, aprimary talkin -circuit at the bridge at each station having a breaktherein and having alsotwo parallel branches, each having a breaktherein, means for closing the former break by the energizing of themagnet, means for closing one of the latter breaks by the removal of thereceiver from its hook, and means for closing the other of the latterbreaks controllable from a distant station, substantiall as described.

5 5 13. A selective te ephonesystem comprising two line-wires, brid estherebetween at the several stations, an e ectromagnet in each bridge, aprimary talkingcircuit at the bridge at each station having a breaktherein and having also two parallel branches, each having a breaktherein, means for closing the former break by the energizing of themagnet, means for closin one of the latter breaks by the removal of t ereceiver from its 65 hook, means, actuated by the said removal,

for preventin the like closure in the other telephone of t e system, andmeans for closing the other of the latter breaks controlla le from adistant station, substantially as described.

14. A selective telephone s stem comprising two line-wires, brid es terebetween at the several stations, an e ectromagnet in each bridge, aprimary talking-circuit at the brid e at each station having a breaktherein, 7 5 and aving also two parallel branches, each having a breaktherein, means for closing the former break b the energizing of themagnet, means for c osing one of the latter breaks by the removal of thereceiver from its hook, means for closin the other of the latter breakscontrollab e from a distant station, a bell-ringing circuit parallelwith the primary talking-circuit and a common battery therein, and ashunt through the bell-magnet coils closed by the removal of thereceiver from its hook, substantially as described.

15. In a selective telephone system, a shunt around the receiver, acircuit passing in parallel through the bell-magnet coils and go thetransmitter, and means for closing said circuit and opening the shunt,substantially as described.

16. A selective telephone system comprising in each tele hone abutton-carrier having 5 fixed buttons t ereon, one for each telephone ofthe system, a corres onding series of pushbuttons, means where hy thepressure u on any push-button looks it to its corres )OI'l ingstationary button thereby closing a reak in a circuit to lace thetelephone on the line, and means or completing the circuit,substantially as described.

17. A selective telephone system comprising in each tele hone abutton-carrier having fixed buttons t ereon, one for each telephone ofthe system, a corresponding series of pushbuttons, means whereby thepressure 11 on any push-button looks it to its corres 10D ing stationarybutton, thereby closing a break in a circuit to place the telephone onthe line, and means, controlled by the pressure of the button, forsubsequentl completing the line through another tele one of the system,substantially as descri ed.

a 18. A selective telephone system comprising in each tele hone abuttomcarrier having fixed buttons t ereon, one for each telephone ofthe system, a corres onding series of pushbuttons, means wher thepressure u on any push-button looks it to its corres non ing stationarybutton thereby closing a reak in a circuit to place the telephone on theline, and means, controlled by the pressure of the button, for closingin the tele hone selected a break in the line, substantial y asdescribed.

19. A selective telephone system comprising in each tele bone abutton-carrier having fixed buttons ereon, one for each telephone of thesystem, clockwork, a rotating contact- 1 o

